The American Journal of Tropical Medicine and Hygiene -
Volume 13,
Issue 3,
May 1964

Volume 13,
Issue 3,
May 1964

The present study concerns the course of experimental arbovirus infection in the gravid Mexican free-tailed bat, Tadarida brasiliensis mexicana. Susceptibility of bats to subcutaneous inoculation with a mosquito isolate (Mosquito-57) of St. Louis encephalitis (SLE) virus, which has been shown to be of low infectivity for the non-pregnant bat, was not increased by the stress of the gestation period. Similarly, susceptibility to infection was not altered in gravid bats inoculated with either a strain of SLE virus isolated from a bird (Flicker Bird-55) or a mosquito isolate (Oct-541) of Japanese B encephalitis (JBE) virus, both of which produce an intense infection in the non-gravid bat.

Transplacental passage of JBE virus occurred in all stages of the gestation period, frequency of fetal infection being increased significantly in late pregnancy. All fetuses were viable when harvested for viral assay and no gross pathology was noted. Distribution of JBE virus in fetal tissues paralleled that in the infected mother bats; virus was found in fetal brown fat, brain, kidneys, and carcass. In contrast to the results with JBE virus, both the highly infectious strain of SLE virus (Flicker Bird-55) and the strain of low infectivity (Mosquito-57) were found to cross the placenta in only one instance.

The significance of studies on experimental arbovirus infection in the gravid bat with regard to the perpetuation of these agents in nature is discussed.

In five out of seven experiments the Highlands J strain of Western equine encephalomyelitis (WEE) was transmitted by contact among infant chicks. Contacts were infected in cramped, limited, and oral environments, but not in fecal or air-borne environments. The infection was probably disseminated by the ingestion of infective oral secretions. Previous investigations conducted on three strains of WEE and eight strains of eastern equine encephalomyelitis are briefly discussed.

The oral administration of a long-acting sulfonamide, sulfamethoxypyridazine, is evaluated in the treatment of trachoma. Four courses of treatment at intervals of 5 days, each course consisting in the administration of 0.5 g once a day for 10 days, proved to cure confirmed cases of trachoma. Concomitant therapy with an antibiotic suspension applied locally produced rapid clinical improvement.

Adenoviruses were isolated from 106 of 204 patients diagnosed as having epidemic keratoconjunctivitis (EKC) who attended the National Taiwan University Ophthalmology Clinic in 1958 and 1959. Serological studies on some of the patients from whom virus was not isolated suggest that most, if not all, were adenovirus infections. Of the adenovirus types isolated, type 8 was by far the most common (72%), while type 4 was the only other type isolated with any frequency (13%). In addition, types 2, 3, 7, 10, 11 and several adenoviruses not types 1 to 18 were isolated. Of the patients in whom follow-up examinations were carried out, 14 of 18 from whom type 8 was isolated developed subepithelial punctate keratitis (SPK), while only 3 of 11 with other types developed this pathognomonic sign. In all, SPK was found in 32 patients including 1 from whom type 4 was isolated, 1 with type 11 and 2 with unclassified types. Type 8 was isolated from throat swabs and from the eyes of 13 patients. The average length of incubation time to isolate 129 strains of type 8 was 27 days as compared to averages of 13 to 20 days for the other types isolated. Conjunctival swab specimens were as good or slightly better than scrapings were for the isolation of adenovirus.

Most EKC cases occurred in the late summer and fall. All ages were involved, but SPK was not seen in patients under 13 years. Detailed clinical findings are reported on a portion of the patients. Most cases were unilateral, had conjunctival petechial hemorrhage and preauricular lymphadenopathy. Only a few had pharyngeal or generalized symptoms. The clinical severity was similar, irrespective of virus type isolated.

Incidence and breeding of the tsetse fly Glossina palpalis (R.-D.) were studied along an 82-mile section of a new road that passes through the forest, broken forest, and grassland regions of the Western Province of Liberia. A potentially dangerous fly population infests the road throughout its length. The roadside incidence of flies is higher in the forest than in the broken forest or in the grassland, but in the latter regions the scarcity of alternative food hosts has encouraged the fly population to feed on man.

The roadside fly breeding-grounds are along the rivers and not around smaller water localities like creeks and water-holes. Maximal breeding of the flies occurred during the driest period of the year, from December to February, with a temporary cessation in breeding during the wettest period, from July to September.

In the grassland the road merges with an endemic focus of sleeping sickness. This has made the roadside fly population hazardous to both local and outside human populations, since the disease seems to have spread linearly along the road since its construction.

Principles of Public Health Administration, by John J. Hanlon, M.S., M.P.H., Director of Community Health Services, City of Philadelphia; Professor and Chairman, Department of Preventive Medicine and Public Health, Temple University School of Medicine, Philadelphia, Pa. 719 pages, illustrated. The C. V. Mosby Company, Saint Louis, Mo. 1964. $11.50.

For the amount of talent that editors Gellis and Kagan have assembled between its covers, this guide to therapy is a good buy. A quick count indicates that almost 250 individuals have contributed to the text; most of them are recognized authorities in their subspecialty fields. The editorial selection of topics to be covered, as well as of the appropriate individual for each topic, is predictably excellent, since Dr. Gellis has for some years edited The Year Book of Pediatrics.

It is assumed by the authors that physicians using this guide have fundamental diagnostic matters well under control and are seeking primarily an expert's present thinking on treatment. Diagnostic discussions are therefore sharply limited. Current Pediatric Therapy does not replace a standard pediatric text; rather, it expands the text's section on treatment into a large compendium of therapy. The book is “perishable” by its nature since treatment is continuously evolving.

Books on Africa are emerging at the same speed as nations of this continent. The Image of Africa is written by a distinguished historian. It is a first class reference book for West Africa and an outstanding product of the trend towards our history of ideas. In fact The Image of Africa describes the British Image of West Africa between 1780 and 1850.

The tropical diseases and their influence on European exploitation in West Africa are dealt with extensively in the chapters on The African's Place in Nature, The Promise and Terror of a Tropical Environment, The Problem of Survival, Tropical Medicine and the Victory of Empiricism as well as in an Appendix on Mortality in West Africa. Pseudo-scientific racism which flowered especially in the XIXth century is analyzed through the entire book and especially in the chapters on Barbarism, Its Physical and Moral Causes and the Racists and Their Opponents.

In tropical regions splenomegaly is common and is not always the result of malarial hyperendemicity. Where malaria has been eradicated cases of splenomegaly still occur to puzzle the clinician. This work analyzes 190 patients suffering from “Tropical or Bengal Splenomegaly” in India. In only 6 cases was a protozoal infection found, in 1 case malaria and in 5, kala azar. In the remainder thrombocytopenic purpura was found in 5, thalassemia in 8 and liver disease or extrahepatic obstruction in 171. So, in Bengal at any rate the great majority of cases of splenomegaly are due to a well recognized cause, usually liver disease. In 81 cases portal hypertension was present. These cases were all fully investigated at operation by splenic venography and liver biopsy; many had splenectomy and shunt operations performed. In those with liver disease post-necrotic cirrhosis was found in the majority.Porto-caval shunt operations produced the most benefit as was to be expected where there was portal hypertension with extra hepatic obstruction.